Drum painting apparatus



Oct. 4, 1966 T. A. MCCOY DRUM PAINTING APPARATUS Filed Nov. 5, 1963 5 Sheets-Sheet 1 INVENTOR. Thomas ,4. McCoy BY Oct. 4, 1966 T. A. MccoY 3,276,422

DRUM FAI NTING APPARATUS Filed Nov. 5, 1963 Z Sheets-Sheet 3 Oct. 4, 1966 T. A, MCCOY 3,276,422

DRUM PAINTING APPARATUS Filed Nov. 5, 1965 I5 Sheets$heet 5 Patented Got. 4-, 13986 3,276,422 DRUM PATNTHNG APPARATUS Thomas A. McCoy, Stockton, Calif., assignor, by mesne assignments, to Cyclops, lino, San Francisco, Calif., a corporation of (Ialifornia Filed Nov. 5, 1963, Ser. No. 321,458 3 Claims. (Cl. 118-321) This invention relates to apparatus for painting the exterior surfaces of metal drums, and particularly to units for painting the exterior faces of the drum ends.

Heretoforebecause of the fact that the drum ends lie in vertical planes while the paint is being applied thereto and the drum is rotatably supported with its axis horizon tal-the paint (as sprayed on as usual) was apt to be deposited on the drum ends in excessive amounts on the central areas thereof, causing the paint to run, while other portions of the drum ends were possibly being insufiiciently covered with the paint.

It is, therefore, the principal object of the present invention to provide a spray painting apparatus for drum ends so constructed that the paint will be sprayed onto the drum ends in a thorough and even manner, and without any one area of such ends having an excessive amount of paint thereon such as would cause the paint to run.

A further object of the invention is to provide separate spray painting units for the opposite ends of the drum, and a single power driven device, separate from said units, which is operatively connected to both the units to control the movement of both units simultaneously and to the same extent.

Anoher object of the invention is to provide, in connection with a supporting structure for a drum of any size, a means adjustably mounting the spray painting units on the structure in such a manner as to accommodate them for efficient operation on a drum of any size, and without having to adjust the position of said power driven device for any adjusted position of the spray units.

A further object of the invention to provide a drum painting apparatus which is designed for ease and economy of manufacture.

A still further object of the invention is to provide a practical, reliable, and durable drum painting apparatus and one which is exceedingly effective for the purpose for which it is designed.

These objects are accomplished by means of such struc ture and relative arrangement of parts as will fully appear by a perusal of the following specification and claims.

In the drawings:

FIG. 1 is a longitudinal elevation of the drum end painting apparatus, showing the spray painting guns in the starting position.

FIG. 2 is an end elevation of the apparatus, with the spray painting gun in the position occupied when paint ly diagrammatic.

FIG. 3 is a similar view, but showing the adjacent spray painting gun in the position occupied when paint is being applied to the central portion of the drum end.

FIG. 4 is a fragmentary sectional plan taken on line 4-4 of FIG. 3.

Referring now more particularly to the drawings and to the characters of reference marked thereon, the apparatus comprises an upstanding frame structure, indicated generally at 1, which includes standards 2 spaced apart a considerable distance greater than the length of a drum 3 to be painted. The drum is turnably supported at its ends and at circumferentially spaced points on pairs of rollers 4- journaled on the frame structure 1 and arranged so that the drum cannot shift in a longitudinal or axial direction. The pair of rollers at one end of the drum is driven in a common direction by chain drive units 5 taking off from the output shaft 6 of a gear box 7; the input shaft 8 of which is operatively connected to an air motor 9. The gear box 7 and motor 9 are mounted on the frame structure 1 in close proximity to said pair of rollers; the pair of rollers at the other end of the drum being connected as a unit to said one pair by their common axial shafts 10 extending therebetween.

The paint applying apparatus comprises a pair of spray painting units, one for each end of the drum and indicated generally at 11. As both units are identical, a description of one such unit will suflice for both.

Each unit 11 comprises a standard form of spray gun 12 having a nozzle 13 disposed in facing relation to the adjacent end 14 of the drum 3 and formed so as to deliver a spray of elongated oval configuration or pattern, as indicated at 15, against said drum end.

The gun 12 is mounted in a block 116 which is adjustably clamped on the upstanding stem 17 of a support 18; said stem being disposed at right angles to the axis of the gun. The support 18 is provided with a stem 19 which is adjustably mounted, both for longitudinal and rotary movement independently, in another block 20; the stem being normally secured by a set screw. The block 20 is fixed on top of a shaft 21 which projects away from the gun 12 and drum 3 while being parallel to the axis thereof. This shaft is journaled in a sleeve 22 Whichintermediate its endsis secured on a bar 23 which projects horizontally in a direction away from the gun l2 and is adjustably clamped against the adjacent standard 2 by a supporting bracket 24 which in turn is vertically adjustable on said standard.

A radial arm 25 depends from the shaft 21 at the outer end thereof; said arm being parallel to the lower depending army 26 of a bellcrank 27 which is turnably mounted on an ear 28 projecting from the bracket 24; the two arms being connected by a rod 29. A11 upstanding rod 30 is adjustably connected to the other arm 31 of the bellcrank 27 and at its upper end is connected to the lower arm 32 of another bellcrank 33 for adjustment lengthwise of said arm. The bellcrank 33 is mounted on said standard 2, and its upper arm 34 is provided at its upper end with a roller 35 which engages a cam 36 disposed in a vertical plane.

The cam 36 is mounted on the output shaft 37 of a gear box 38 supported on the frame structure 1. The input shaft 39 of the gear box is driven by an air motor 40 mounted on said frame structure. The spray painting units 11 are both actuated from the one driven cam 36 by means of a shaft 41 journaled in the standards 2 and extending between and forming the pivotal mount for and a rigid connection between the two opposed bellcranks 33 of the two units 11.

The cam 36, which is symmetrical on opposite sides of its major axial line L, is formed on each side with an initial dwell edge portion 42, concentric with the shaft 37, and with a further and working edge portion 43 projecting in gradually deviating relation to said shaft 37. The relative positions of the cam 36 and each gun 12 are such that when the gum. is disposed with the spray pattern 15 extending circumferentially of the drum end 14 adjacent the periphery thereof, as shown in FIG. 2, the roller 35 is riding on the dwell edge 42 of the cam. The speed of rotation of the drum is so coordinated to the speed of the cam that the roller 35 will remain on the dwell edge 42 of the cam during a full rotation of the drum whereby a strip or course of paint will be applied to the drum end inwardly from the periphery thereof for the full circumferential extent of the drum.

During the succeeding rotation of the drum and cam, the roller 35 rides on the working edge 4-3 of the cam. Through the operating connections between the bellcrank 33 and the spray gun support 18, the spray gun 12 is gradually tilted and at the same time moved radially inward of the drum end 14. Consequently, the spray pattern 15 is similarly tilted until, as the roller 35 engages the far end of the working edge 43 of the cam, said spray pattern is moved to a position nearly radially of the drum, with the narrow end only of such pattern overlapping the central area of the drum, as shown in FIG. 3.

The working edge 43 of the cam 3d is designed so that the movement of the spray gun radially of the drum increases in speed as the gun approaches the center of the drum end. This feature compensates for the decrease in size of the area being painted as the drum rotates and the spray gun moves radially inward.

By reason of the foregoing spray gun control arrangement, the drum end will be completely painted in an even manner, without any excessive amount of paint being applied to the central zone of said drum end.

Upon the roller engaging the far end of the working edge 43 of the cam and completion of the painting of the drum. end, the valve 44- in the compressed air line 45 leading to the gun 12 is closed so that the spray from the gun ceases. A further half-turn of the cam then returns the spray gun-and the cam-to their initial position, at which time the valve 46 in the air line 47 to the air motor 40 is closed. The cam and spray gun are then retained in an inactive condition until the drum just painted has been removed from its supported position on the rollers 3 and another drum to be painted has been mounted thereon; such rollers turning continuously. The valves 44 and 46 are then simultaneously opened so that the cam will start to turn and the spray gun will begin to operate at the same time. The valves may, of course, be arranged with mechanisms or devices which will automatically operate them at the proper time.

While the description of operation is related mainly to one spray gain and the adjacent drum end only, it 18 to be understood that actually both spray guns, at the opposite ends of the drum, are functioning in the same manner and at the same time. This is, of course, by reason of the fact that the two spray gun actuating or control mechanisms are simultaneously operated by the shaft 41.

Because of the adjustability of the spray guns and their operating and mounting means relative to the fixcrhposn tion control cam 36, the guns may be readily positioned for efficient action on drums of different diameters.

-In connection with the drum end painting units which are the subject of this invention, a separate and conventional painting unit is mounted on the frame structure 1 for movement back and forth along the drum to paintthe exterior longitudinal surface thereof at the same time the ends are being painted. However, as such separate painting unit forms no part of the present invention, no showing of the same has been made.

It will be noted that air motors have been specified as being the power means to actuate the drum supporting rollers and the spray gun control mechanisms, rather than electric motors. This is to avoid the possibility of sparks being created by the operation of the motors, and which might ignite inflammable fumes from the spray guns.

From the foregoing description, it will be readily seen that there has been produced such a device as substantially fulfills the objects of the invention, as set forth herein.

While this specification sets forth in detail the present and preferred construction of the device, still in practice such deviations from such detail may be resorted to as do not form a departure from the spirit of the invention, as defined by the appended claims.

Having thus described the invention, the following is claimed as new and useful and upon which Letters Patent is desired:

1. An apparatus for spray-painting the vertically disposed end of a drum turnably mounted with its axis horizontal, the apparatus comprising a spray gun facing said drum end, a nozzle on the gun adapted to deposit an elongated spray pattern on said drum end, means movably mounting the gun so that said spray pattern is initially positioned with its major axis disposed substantially circumferentially of the drum end adjacent the periphery thereof, and control means acting on said gun mounting means so that the gun and its spray pattern is moved radially inward of the drum end from said initial position to a final position at which said major axis of the spray pattern is disposed substantially radially of the drum with one end of the pattern overlying the central portion of the drum end; there being means to rotate the drum, and said gun mounting means comprising a support for the gun, a rigid stem projecting from the support at right angles to the axis of the gun, a relatively stationary block, and means mounting the stern in the block for adjustment both longitudinally and rotationally about its own axis, independently.

2. An apparatus for spray-painting the vertically disposed end of a drum turnably mounted with its axis horizontal, the apparatus comprising a spray gun facing said drum end, a nozzle on the gun adapted to deposit an elongated spray pattern on said drum end, means to rotate the drum about its axis at a constant speed, a support for the gun, a stem projecting from the support at right angles to the axis of the gun, a block in which the stem is turnably and longitudinally adjustable, a shaft rigid with the block below the same and parallel to the axis of the drum to one side of and above such axis, an arm rigid with and depending from the shaft, a horizontal bar in which the shaft is journaled projecting away from the stem and gun, a bracket in which the bar is supported for horizontal adjustment, a supporting structure for the apparatus including a fixed standard on which the bracket is vertically adjustably supported, a horizontal-axis bellcrank mounted on the bracket between said shaft and the standard, the bellcrank having an upper arm and a lower arm the latter being substantially parallel to the first named arm, a rod connecting said lower and first named arms, another bellcrank mounted on the standard above the bracket, said other bellcrank including a lower arm and an upper arm, a rod extending between and connected to the upper and lower arms of the firs-t and second named bellcranks, respectively, a roller mounted on the outer end of the upper arm of said other bellcrank, a constant speed cam turnably mounted on the supporting structure with its axis of rotation parallel to the drum axis, and means to rotate the cam through a half turn for each full painting of the drum end; the cam having a roller engaging edge which includes, for one-half the peripheral extent of the cam, a portion concentric with the axis of rotation of the cam and a following portion disposed relative to said axis to impart turning movement to said other bellcrank at a gradually increasing speed with the constant speed of the cam; the roller engaging the first named cam edge portion when the gun is disposed so that the spray pattern engages the drum end adjacent the periphery thereof with the major axis of the spray pat-tern disposed substantially circumferentially of the drum, the circumferential extent of the first named cam edge portion relative to the speed of rotation of the drum and cam being such as to maintain the gun in a stationary position with a full rotation of the drum.

3. An apparatus for spray-painting the vertically disposed end of a drum turnably mounted with its axis horizontal, the apparatus comprising a spray gun facing said drum end, a nozzle on the gun adapted to deposit an elongated spray pattern on said drum end, means movably mounting the gun so that said spray pattern is initially positioned with its major axis disposed substantially circumferentially of the drum end adjacent the periphery thereof, and control means acting on said gun mounting means so that the gun and its spray pattern is moved radially inward of the drum end from said initial position to a final position at which said major axis of the spray pattern is disposed substantially radially of the drum with one end of the pattern overlying the central portion of the drum end; there being means to rotate the drum, and said control means including a driven rotary cam having a peripheral edge, a cam-edge engaging element operatively connected to the gun mounting means to so move the gun, the initial portion of said cam edge being concentric with the axis of rotation of the cam, the drum being rotated at a predetermined speed, and means to rotate the learn at a predetermined speed; the circumferential extent of said initial portion of the cam edge being such relative to the speed of rotation of the drum and cam as to maintain the gun at said initial position during a full rotation of the drum, and the following portion of said cam edge being arranged to impart turning movement to the gun at a gradually increasing speed with a constant speed of the cam.

References Cited by the Examiner UNITED STATES PATENTS 1,866,100 7/1932 Hach 118 -316 2,109,619 3/1938 Hurd 118-316 2,245,932 6/1941 Miller 11s 323 2,519,102 8/1950 Bergstein 53-39 10 2,613,635 10/1952 MacWilliarn 118-316 DANIEL BLUM, Primary Examiner. 

1. AN APPARATUS FOR SPRAY-PAINTING THE VERTICALLY DISPOSED END OF A DRUM TURNABLY MOUNTED WITH ITS AXIS HORIZONTAL, THE APPARATUS COMPRISING A SPRAY GUN FACING SAID DRUM END, A NOZZLE ON THE GUN ADAPTED TO DEPOSIT AN ELONGATED SPRAY PATTERN ON SAID DRUM END, MEANS MOVABLY MOUNTING THE GUN SO THAT SAID SPRAY PATTERN IS INITIALLY POSITIONED WITH ITS MAJOR AXIS DISPOSED SUBSTANTIALLY CIRCUMFERENTIALLY OF THE DRUM END ADJACENT THE PERIPHERY THEREOF, AND CONTROL MEANS ACTING ON SAID GUN MOUNTING MEANS SO THAT THE GUN AND ITS SPRAY PATTERN IS MOVED RADIALLY INWARD OF THE DRUM END FROM SAID INITIAL POSITION TO A FINAL POSITION AT WHICH SAID MAJOR AXIS OF THE SPRAY PATTERN IS DISPOSED SUBSTANTIALLY RADIALLY OF THE DRUM WITH ONE END OF THE PATTERN OVERLYING THE CENTRAL PORTION OF THE DRUM END; THERE BEING MEANS TO ROTATE THE DRUM, AND SAID GUN MOUNTING MEANS COMPRISING A SUPPORT FOR THE GUN, A RIGID STEM PROJECTING FROM THE SUPPORT AT RIGHT ANGLES TO THE AXIS OF THE GUN, A RELATIVELY STATIONARY BLOCK, AND MEANS LONGITUDINALLY AND ROTATIONALLY ABOUT ITS OWN AXIS, INDEPENDENTLY. 